1. Field of the Invention
The present invention relates to tendon anchors. More specifically, it relates to tendon anchors utilized to attach tendons to one or more bones without sutures and through a single bore drilled into the bone.
2. Description of the Prior Art
The need to effectively and efficiently attach a tendon to a bone is absolutely critical in a number of orthopedic surgical procedures. The most common current practice is to utilize a device called a suture anchor to attach a suture to the bone and thereafter tie the tendon to the suture thereby making the attachment of the tendon to the bone. Examples of this practice are set forth in U.S. Pat. Nos. 5,961,538; 5,944,724; 5,906,624; and 5,904,704. While such techniques are reasonably effective, the use of suture anchors is overly time consuming and creates unnecessary risks of failure. For example, the suture may become detached from the anchor or the tendon and the process of suturing the tendon to the anchor may actually weaken the strength of the tendon itself or cause it to tear. It is believed that a better technique would involve a direct attachment of the tendon itself to a tendon anchor which is secured within the bone.
One known process which is believed to be a step in the right direction is disclosed in a publication entitled “Bone Mulch Screw/WasherLoc Device For the New Millennium” published by Arthrotek, a Biomet Company. The publication is undated but is believed to have been published in early 2000 and not earlier than the later part of 1999. This publication discloses an ACL reconstruction technique in which a tendon is ultimately attached directly to the bone by means of tendon anchors. While sutures are not utilized to attach the tendon to the bone, the process still requires the use of a suture (pp. 9-10) attached to one end of the tendon to pull the tendon over a transverse cross beam of the femoral anchor. Such a process is overly complex and unnecessarily time consuming.
Further, the Arthotek device itself is overly complex and utilizes at least one tendon anchor which requires drilling two separate bores into the femur, one longitudinally through which the tendon is threaded and one transversely to provide a cross beam over which the tendon is passed (see FIG. 25 of publication). Drilling an extra bore into the bone takes more time, requires precision to make certain that the two bore holes intersect, causes increased trauma to the patient and can weaken the overall structure of the bone. Thus, while this technique provides an improvement over prior art devices which require suturing a tendon to a suture anchor (sometimes called bone anchor), there remains a need for a simple, easy to install tendon anchor which does not require sutures at all during the installation procedure and which only require the drilling of a single bore into the bone.